Multiple adjacent tapes are commonly found in folders used in printing presses such as web offset printing presses. Tensioning systems for multiple adjacent tapes require adjustment when the tapes are installed or replaced, or to periodically tension the tapes as they stretch. Generally, each of the multiple tapes is mounted on a roller connected to a tensioner arm and the tapes must each be under similar tensions. For example, when an individual tape breaks, the new tape must be installed and manually adjusted so that its tension is equivalent to the others. Even if tapes do not need to be replaced, normal expansion or stretching requires frequent adjustment to maintain constant tension in the tapes. Manual adjustment normally requires special tools to ensure that the tension is correct, is difficult to perform precisely, and is made more difficult due to limited mobility of the rollers which hold or support the tapes. Manual adjustment thus adds cost to the assembly, repair, or maintenance of the machine, and normal stretching of the tapes requires that the system be monitored and maintained to assure proper machine performance.
For example, in a conventional printing press folder, such as the Heidelberg Harris PFF-3 folder manufactured by Heidelberg Harris, Inc. of Dover, N. H., signatures traveling at relatively high speeds are accelerated, via a friction contact with multiple adjacent tapes of the folder, for delivery into a fan wheel or deceleration device. There the signature is slowed down and prepared for further processing. In such a conventional folder, a problem arises with tape changes as there is little room to work in the folder, thus necessitating movement of (e.g., raising up) for example, the lead-in rolls to facilitate tape changes. To compensate for the slack in the tapes created by raising up the lead-in rolls, generally tension is applied to the tapes by, for example, operating a pneumatically operated tensioner against all of the tapes.
In such a system, however, all of the tensioner arms are clamped to a common shaft and independent movement of the arms (such as, for example, to replace a particular, individual tape, to perform maintenance, or to clear a paper jam) is not possible without tools.